Device for the pneumatic squeezing of a continuously moving thread

ABSTRACT

This invention relates to a device for the pneumatic squeezing of a continuously moving thread. The device comprises a substantially cone-shaped squeezing chamber traversed axially by the thread and fed tangentially with a squeezing fluid. It is more especially intended for the squeezing of a textile thread.

United States Patent Rose DEVICE FOR THE PNEUMATIC SQUEEZING OF A CONTINUOUSLY MOVING THREAD Jacques l-l. Rose, Saint Quentin, France O.P.l. Textile, rue de Saint Quentin, France Filed: July 23, 1974 Appl. No.: 491,036

Inventor:

Assignee:

Foreign Application Priority Data July 24, 1973 France 73126980 U.S. Cl 28/62; 34/23 Int. Cl. D02] 13/00; F26b 5/04 Field of Search 28/61, 62, 1.4; 68/DlG. 1, 68/20; 34/010. 14, 23

[ July 1, 1975 {56] References Cited UNITED STATES PATENTS 2,740,202 4/l956 Fowle 34/DlG. 14 3,095,343 6/1963 Berger 28/l.4 X 3,7l8,012 2/1973 Vinas 68/DlG. 1 3,724,088 4/1973 Lefebvre et al 34/23 X Primary ExaminerLouis K. Rimrodt Attorney, Agent, or Firm-Fitzpatrick, Cella, Harper & Scinto 5 7] ABSTRACT This invention relates to a device for the pneumatic squeezing of a continuously moving thread. The device comprises a substantially cone-shaped squeezing chamber traversed axially by the thread and fed tangentially with a squeezing fluid. It is more especially intended for the squeezing of a textile thread.

4 Claims, 1 Drawing Figure l 11 i l DEVICE FOR THE PNEUMATIC SQUEEZING or A coNTlNuousLY MovlNc THREAD The present invention 'relates to a device forthe squeezing of a continuously moving thread by means of compressed air. The device is 'more especiallyadapted to the squeezing of textile threads.

Although the treatments. of textile threadssuch as bleaching, dyeing, etc. have been effected for a long time on bobbins or hanks, .i.t is known that it is advantageous both for the quality of treatment and for the production speed to use processes and devices for the continuous treatment of threads. y i i I Most of these treatments require either as an intermediate stage or as the final stage of treatment a more or less complete squeezing of the thread also to be carried out in a continuous manner. l

Numerous devices have been proposed, the best known amongst which use an air current circulating close to the thread. In such devices, the thread is generally badly guided coming thus into contact with-various mechanical parts which entails the formation of bunches of torn-off fibrils and the destruction of certain properties of the thread. Moreover, these devices generally require a very high air pressure to allow an efficient squeezing, which is expensive and often bad for the thread.

By textile thread is meant any flexible product whose cross-section is of small dimensions in relation to its length whether it is natural or synthetic and made up of continuous or discontinuous fibres.

The present invention has as its aim to realize a device for the pneumatic squeezing of a textile thread which is efficient at a low operating pressure and which does not harm the thread. To this end, the device comprises a substantially cone-shaped squeezing chamber traversed axially by the thread which enters the chamber at the end having the smallest cross-section and leaves the chamber at the end having the largest crosssection. A pipe opening out tangentially to the inner wall of the chamber into the part of the chamber having the largest cross-section, feeds the chamber with compressed air to which is imparted a helical motion, similar to a cyclone.

The inlet orifice through which the thread enters the chamber is in convergent-divergent form. The outlet orifice is preferably constituted by a tube which extends axially in one part of the chamber and surrounds the thread, serving as a guide and offering protection. According to the type of thread that is to be treated, the tangential feed is effected in such a way as to give the air circulating in the chamber an either S or Z direction of rotation.

The attached drawing shows schematically the pneumatic squeezing device in accordance with the invention.

The thread 1 is made to traverse axially this squeezing device in the direction of the arrow. The device comprises mainly a chamber 2 provided with an inlet orifice 3 and an outlet orifice 4 for the passage of the thread, these orifices being aligned axially. This chamher 2 is substantially cone-shaped. The inlet orifice 3 is placed in the part of the chamber 2 having the smallest cross-section and has been given convergent-divergent shape, the neck of which has a diameter close to that of the thread being treated. The outlet orifice 4, placed in the part of the chamber 2 having the largest crosssection, in fact constituted by a capillary tube 5 which is placed in the axis of the chamber 2, inside the same, on a part of the path followed by the thread in the chamber and which surrounds the thread. The inner diameter of this tube is close to that of the thread being treated and its function will be specified further This charnber 2 comprises a pipe 6 opening out into the "part of the chamber having the largest crosssec ti onfwhich is the exit area of the thread. This pipe is substantially tangent to the inner wall of the chamber 2. ltslaxis is preferably perpendicular to the axis of the chamber. This pipe is connected to a compressed air feed-device which is not shown here.

The end of the chamber 2 having the smallest crosssection is connected by the convergent-divergent orifice 3 to a recovery chamber 7 which may be of any shape and which comprises a pipe 8 for the evacuation of the product removed from the thread 1 by squeezing, which product may eventually be recycled.

The thread I having previously undergone a treatment of impregnation, consisting of a dye bath for example, is driven at high speed, by means not shown here, through the squeezing device according to the present invention. After having traversed the recovery chamber 7, it penetrates through the inlet orifice 3 into the chamber 2. After having traversed the chamber 2, it leaves it through the outlet orifice 4 after having traversed the tube 5.

The chmber 2 is fed with compressed air by the pipe 6. Any other fluid being able to ensure an efficient squeezing or even a treatment may be used. Owing to the cone-shaped chamber 2 and the tangential feed, the air is set into a whirling movement and escapes through orifice 3. The direction of rotation will be either S or Z, depending on the position of the pipe 6. As happens in a cyclone, part of this air tends to circulate backwards along the axis of the chamber and to escape through the orifice 4. This effect is partially limited by the presence of the tube 5 and by its small inner diameter determined by that of the thread being treated. The air escaping through the neck 3 produces at this point an efficient squeezing of the thread which is increased further by the presence of the divergent configuration at the inlet of the recovery chamber 7. Moreover, one part of the residual humidity of the thread is carried along by the current of air escaping through the outlet orifice 4, so that the thread is thus perfectly squeezed at the outlet of the chamber 2.

The tube 5 plays in fact a very important part. As outlined above, it limits the quantity of air escaping through the orifice 4 contributing thereby to a good squeezing at 3. Moreover, it ensures the guidance of the thread in the chamber 2 by causing the thread to remain in the axis of the whirling motion, it prevents it from rotating and from coming into contact with the inner surface of the chamber 2, which would obviously be harmful. Finally, it protects the thread against the action of the compressed air at the moment when it penetrates into the chamber 2 and is not yet in rotation. in fact, it has become apparent that in absence of this tube the action of the compressed air on the thread causes superficial fibrils to be torn off and and to accuallows moreover this deterioration of the thread and of the squeezing device to be avoided. The length of this tube 5 depends on the pressure of the compressed air, on the running speed of the thread, on the desired squeezing rate. on the shape of the squeezing chamber and on the diameters of the entrance and exit of the air.

It has been found that a low compressed air feeding pressure. ofthe order of 1 bar, is sufficient to ensure a correct squeezing rate. even in case of very high running speeds of the thread, of the order of 800 or 1000 meters per minute. Moreover, the squeezing rate can easily be modified by making the pressure of the compressed air to vary The thread does not suffer any harm owing to the fact that no superficial fibrils are torn off and that it does not come into contact with the mechanical parts of the device.

Of course, the invention is not limited to the embodiment that has been described herein, but covers on the contrary all the variants thereof.

What is claimed is:

l. A device for the pneumatic squeezing ofa continuously moving thread comprising a squeezing chamber provided with inlet orifice and an outlet orifice for the thread, these orifices being aligned in the axis of said chamber. and a pipe for feeding the chamber with squeezing fluid, characterised in that the chamber is substantially cone-shaped the inlet orifice for the thread is placed at the end of the chamber having the smallest cross-section the outlet orifice for the thread is placed at the end of the chamber having the largest cross-section the squeezing fluid feed pipe communicates with that part of the chamber having the largest cross section, tangentally to the inner wall of the chamher.

2. A device in accordance with claim 1, characterised in that the inlet orifice for the thread is in the form of a convergent-divergent.

3. A device in accordance with claim 1, characterised in that the tangential feed of the chamber is effected with an S direction of rotation.

4. A device in accordance with claim 1, characterised in that the tangential feed of the chamber is effected with a Z direction of rotation.

* i IF 

1. A device for the pneumatic squeezing of a continuously moving thread comprising a squeezing chamber provided with inlet orifice and an outlet orifice for the thread, these orifices being aligned in the axis of said chamber, and a pipe for feeding the chamber with squeezing fluid, characterised in that the chamber is substantially cone-shaped the inlet orifice for the thread is placed at the end of the chamber having the smallest cross-section the outlet orifice for the thread is placed at the end of the chamber having the largest cross-section the squeezing fluid feed pipe communicates with that part of the chamber having the largest cross-section, tangentally to the inner wall of the chamber.
 2. A device in accordance with claim 1, characterised in that the inlet orifice for the thread is in the form of a convergent-divergent.
 3. A device in accordance with claim 1, characterised in that the tangential feed of the chamber is effected with an S direction of rotation.
 4. A device in accordance with claim 1, characterised in that the tangential feed of the chamber is effected with a Z direction of rotation. 